Answer:
You are correct, it is (3) the ball is in motion as it rolls down the slope.
Explanation:
For number 1 it would make sense because how would the student be in motion if he is just standing there throwing the ball down the slope, not himself.
For number 2 still wouldn't make so much sense since we are talking about the ball being in motion not the student.
For number 3 it seems the most reasonable because the ball is in motion as it is rolling down the slope.
For number 4 it doesn't make sense for a ball to lose its shape just by rolling, also even if you're like: "oh, but what if its leaking air or has a hole??" well easy then. It STILL wouldn't matter because in the sentence it never specifies it has a "hole" or is "leaking air" therefore this answer is wrong.
YOUR ANSWER IS number 3.
The answer is c, but I'm not sure, just so you know
To solve this problem we will apply the concepts related to the conservation of momentum. Momentum can be defined as the product between mass and velocity. We will depart to facilitate the understanding of the demonstration, considering the initial and final momentum separately, but for conservation, they will be later matched. Thus we will obtain the value of the mass. Our values will be defined as
Initial momentum will be
After collision
Final momentum
From conservation of momentum
Replacing,